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/*
* Author: Jon Trulson <jtrulson@ics.com>
* Copyright (c) 2015 Intel Corporation.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include <iostream>
#include <string>
#include <stdexcept>
#include "hm11.h"
using namespace upm;
using namespace std;
static const int defaultDelay = 100; // max wait time for read
HM11::HM11(int uart)
{
m_ttyFd = -1;
if ( !(m_uart = mraa_uart_init(uart)) )
{
throw std::invalid_argument(std::string(__FUNCTION__) +
": mraa_uart_init() failed");
return;
}
// This requires a recent MRAA (1/2015)
const char *devPath = mraa_uart_get_dev_path(m_uart);
if (!devPath)
{
throw std::runtime_error(std::string(__FUNCTION__) +
": mraa_uart_get_dev_path() failed");
return;
}
// now open the tty
if ( (m_ttyFd = open(devPath, O_RDWR)) == -1)
{
throw std::runtime_error(std::string(__FUNCTION__) +
": open of " +
string(devPath) + " failed:" +
string(strerror(errno)));
return;
}
}
HM11::~HM11()
{
if (m_ttyFd != -1)
close(m_ttyFd);
}
bool HM11::dataAvailable(unsigned int millis)
{
if (m_ttyFd == -1)
return false;
struct timeval timeout;
// no waiting
timeout.tv_sec = 0;
timeout.tv_usec = millis * 1000;
int nfds;
fd_set readfds;
FD_ZERO(&readfds);
FD_SET(m_ttyFd, &readfds);
if (select(m_ttyFd + 1, &readfds, NULL, NULL, &timeout) > 0)
return true; // data is ready
else
return false;
}
int HM11::readData(char *buffer, int len)
{
if (m_ttyFd == -1)
return(-1);
int rv = read(m_ttyFd, buffer, len);
if (rv < 0)
{
throw std::runtime_error(std::string(__FUNCTION__) +
": read() failed: " +
string(strerror(errno)));
return rv;
}
return rv;
}
int HM11::writeData(char *buffer, int len)
{
if (m_ttyFd == -1)
return(-1);
// first, flush any pending but unread input
tcflush(m_ttyFd, TCIFLUSH);
int rv = write(m_ttyFd, buffer, len);
if (rv < 0)
{
throw std::runtime_error(std::string(__FUNCTION__) +
": write() failed: " +
string(strerror(errno)));
return rv;
}
tcdrain(m_ttyFd);
return rv;
}
bool HM11::setupTty(speed_t baud)
{
if (m_ttyFd == -1)
return(false);
struct termios termio;
// get current modes
tcgetattr(m_ttyFd, &termio);
// setup for a 'raw' mode. 81N, no echo or special character
// handling, such as flow control.
cfmakeraw(&termio);
// set our baud rates
cfsetispeed(&termio, baud);
cfsetospeed(&termio, baud);
// make it so
if (tcsetattr(m_ttyFd, TCSAFLUSH, &termio) < 0)
{
throw std::runtime_error(std::string(__FUNCTION__) +
": tcsetattr() failed: " +
string(strerror(errno)));
return false;
}
return true;
}
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